In recent years, as the electronic devices are becoming smaller and thinner, the electronic components equipped in these electronic devices are also required to be downsized. Especially, with regard to the multilayer ceramic capacitor, it is limited by the mounting area of the electronic components and requires a high capacitance in a downsized product according to the needs for thin consumer devices.
Based on such a market demand, the multilayer ceramic capacitor should ensure a capacitance big enough and must be downsized. Here, the electrostatic capacitance of the multilayer ceramic capacitor is represented by formula 1.
                    C        =                              (                                                            ɛ                  r                                ×                                  ɛ                  0                                ×                S                            d                        )                    ×          n                                    [                  Formula          ⁢                                          ⁢          1                ]            
C: electrostatic capacitance; ∈r: relative permittivity; ∈0: vacuum permittivity.
S: overlapping area of internal electrodes; d: thickness of the dielectric ceramic layer;
n: number of laminated layers.
As shown in the formula 1, in order to increase the electrostatic capacitance of the multilayer ceramic capacitor, if the overlapping area of the internal electrodes are considered to be almost constant, adjustments can be made to increase the inherent relative permittivity of the ceramic material, to decrease the thickness of the dielectric ceramic layer, or to increase the number of laminated layers by thinning the thickness of the internal electrode layer.
However, as the relative permittivity is an inherent value depending on the substance, large improvement cannot be expected if no new dielectric material is discovered. Therefore, improvements on designs are required such as decreasing the thickness of the internal electrode layers or the thickness of the dielectric ceramic layers. In recent years, a multilayer ceramic capacitor is required which is formed by internal electrode layers and dielectric ceramic layers with a thickness of 0.50 μm or less. And the biggest problem is a technique for suppressing structural defects such as cracks or delamination or the like which tend to occur along with the thinner of the layer in the internal structure.
For example, as a conventional technique to suppress delamination of products such as the multilayer ceramic capacitors, methods have been proposed with the following method in Patent Document 1 as a representative one. That is, generating electrode discontinuity portions in the internal electrode layer, wherein the electrode discontinuity portions are made of dielectric ceramic particles with their sizes grown to the extent of the thickness of the internal electrode layer, and making the electrode discontinuity portions have an anchor function like pillars connecting the dielectric ceramic layers arranged respectively on and under the internal electrode layers.
In addition, Patent Document 2 has disclosed a method to improve the bonding strength between the internal electrode layers and the dielectric ceramic layers by increasing the contact area with the dielectric ceramic layers by disposing acicular segregates in the discontinuity portion of the internal electrode layers, wherein the acicular particles run through the electrode discontinuity portions and bridge the dielectric ceramic layers.